Adjustable pinhole for a laser scanning microscope

Abstract

An adjustable pinhole, in particular for a beam path for illumination and/or detection in a laser-scanning microscope. The pinhole consists of at least two planar basic modules, which have frame-like joints, on which at least one blade is arranged in a displaceable manner in one direction, whereby the basic component advantageously contains at least one integrated, preferably optical or electromagnetic actuator. A device is provided at the blade, or connected with it, for preferably optical or electromagnetic detection of the position, and is provided, advantageously, with two asymmetric apertures, with mutually opposite orientation, for optical detection of the position, whereby in front of or behind the apertures, a slit is provided, oriented preferably at a right angle to the direction of displacement, and the quantity of light passing through the slit is detected separately for each aperture.

1. An adjustable pinhole for at least one of the illumination beam path and the detection beam path of a laser scanning microscope, the pinhole comprising at least two spaced-apart, planar basic modules, wherein each basic module includes:
 at least one inner base plate, 
 an outer frame 
 elastic webs holding the at least one inner base plate to the outer frame at elastic junction points, 
 at least one blade mounted on a corresponding inner base plate, the at least one blade being linearly displaceable and having a blade edge having a linear direction of displacement perpendicular to a slit aperture located before or behind the basic module, 
 two oppositely-oriented, asymmetric apertures coupled to each blade and positioned relative to the slit aperture to allow passage of beams from at least one light source illuminating the slip aperture, for optically detecting the position of the blade. 
 
     
     
       2. The pinhole according to  claim 1 , wherein a basic module includes two mutually displaceable blades, which form a parallel intermediate space with respect to each other. 
     
     
       3. The pinhole according to  claim 1 , comprising two basic modules, each basic module being provided with two blades, and the direction of the displacement of the blade edges of one of the two basic modules forms an angle of about 90 degrees with respect to the direction of the displacement of the blade edges of the other of the two basic modules. 
     
     
       4. The pinhole according to  claim 1 , wherein the apertures comprise two triangles with mutually opposite orientation. 
     
     
       5. The pinhole according to  claim 1 , further comprising electromagnetic actuators for actuating displacement of the at least one blade. 
     
     
       6. The adjustable pinhole according to  claim 1 , further comprising:
 at least one light source for illuminating the asymmetric apertures; 
 an aperture plate arranged symmetrically with respect to the at least two planar basic modules, the slit aperture being arranged in the aperture plate, and 
 detector means for separately detecting for each of the asymmetric apertures the quantity of light from the beams passing through the asymmetric apertures. 
 
     
     
       7. The device according to  claim 6 , wherein the asymmetric apertures form part of an integrated optical measuring system in a closed control circuit for controlling the position and the opening of the blades. 
     
     
       8. An adjustable pinhole for at least one of the illumination beam path and the detection beam path of a laser scanning microscope, the pinhole comprising at least two spaced-apart, planar basic modules, wherein each basic module includes:
 at least one inner base plate, 
 an outer frame, 
 elastic webs incorporated with the outer frame and holding the at least one inner base plate to the outer frame, the elastic webs and the outer frame having juncture points therebetween, the juncture points being provided with recesses therein, 
 at least one blade mounted on a corresponding inner base plate, the at least one blade being linearly displaceable and having a blade edge having a linear direction of displacement perpendicular to a slit aperture located before or behind the basic module, 
 two oppositely-oriented, asymmetric apertures coupled to each blade and positioned relative to the slit aperture to allow passage of beams from at least one light source illuminating the slip aperture, for optically detecting the position of the blade.